What does Transaction mean?
A movement of data or tokens from one account to another.
The basic idea of a blockchain database is to keep track of the Current Ledger State, for all the accounts on the blockchain. Transactions, or requests to move something in one account to another, are submitted to a node in the blockchain validation network as candidate transactions. If they are approved (or validated), then they are written into a block which is updated to reflect a new Current Ledger State.
The blockchain protocol should be constructed in such a way that all invalid transactions (such as those that try to spend more tokens than the account holds or request transfer of tokens that aren’t theirs) are declared invalid and eliminated from the candidate transactions for that block.
Warning: If a user sends a valid transaction (there are enough tokens in the account, the transaction is properly assigned with the authority to access that account) to an unintended receiving account, that transaction is irreversible. Therefore, a user has the responsibility to check carefully before sending a transaction of any size and keep their private keys safe to prevent unauthorized access to their accounts.
Although it is easy to conceptualize tokens in a blockchain account, such as a number of coins in a bank account, a blockchain account may contain all kinds of data (probably encrypted). An authorized transaction is simply a request by an account owner to transfer balances between accounts.
The current ledger state of an account is simply the sum of all the valid transactions into and out of the account added to the initial account balance. Thus, the current ledger state in a block is the list, however kept or recorded, of all the accounts and their current states.
Used in a Sentence:
Blockchains are a very specific form of sequentially constructed databases that track the effect transactions have on a Current Ledger State.
Last Updated: March 21, 2021